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[PATCH v28 09/11] Add support for min/max aggregates for IVM 259+ messages / 2 participants [nested] [flat]
* [PATCH v28 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index c8aa558f2e..c40ea6b2bc 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1312,6 +1312,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index aa6bf2694a..fa65e4aeb0 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -73,6 +73,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + OverrideSearchPath *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -109,6 +137,7 @@ typedef struct MV_TriggerTable TupleTableSlot *slot; /* for checking visibility in the pre-state table */ } MV_TriggerTable; +static HTAB *mv_query_cache = NULL; static HTAB *mv_trigger_info = NULL; static bool in_delta_calculation = false; @@ -169,6 +198,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -177,17 +209,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort); /* @@ -2102,6 +2147,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2183,6 +2230,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2212,6 +2270,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2230,10 +2290,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2425,6 +2493,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2527,19 +2659,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2554,10 +2711,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2565,10 +2723,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2751,6 +2924,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -2784,6 +3300,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -2792,6 +3315,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + OverrideSearchPathMatchesCurrent(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetOverrideSearchPath(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.25.1 --Multipart=_Thu__1_Jun_2023_23_59_09_+0900_/G5+8nG46.f1T42K Content-Type: text/x-diff; name="v28-0010-Add-regression-tests-for-Incremental-View-Mainte.patch" Content-Disposition: attachment; filename="v28-0010-Add-regression-tests-for-Incremental-View-Mainte.patch" Content-Transfer-Encoding: 7bit ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v37 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 45a30309951..ed67f399b7c 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1332,6 +1332,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Fri__29_May_2026_23_14_17_+0900_Te0o73X2VqYK57Gd Content-Type: text/x-diff; name="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v37-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v38 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index 35e124694ab..540d9e3d5c8 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1341,6 +1341,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 710224aa994..3b3871c49e2 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -121,6 +149,7 @@ typedef struct DroppedImmvInfo } DroppedImmvInfo; static HTAB *mv_trigger_info = NULL; +static HTAB *mv_query_cache = NULL; static HTAB *dropped_immv = NULL; static HTAB *LastIvmUpdateHash; @@ -210,6 +239,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -218,17 +250,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort, SubTransactionId subxid); static void setLastUpdateXid(Oid immv_oid, FullTransactionId xid); @@ -2343,6 +2388,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2424,6 +2471,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2453,6 +2511,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2471,10 +2531,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2666,6 +2734,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2768,19 +2900,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2795,10 +2952,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2806,10 +2964,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2992,6 +3165,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -3025,6 +3541,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -3039,6 +3562,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.43.0 --Multipart=_Wed__1_Jul_2026_00_04_01_+0900_OVSy2WWK_9aByzDJ Content-Type: text/x-diff; name="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v38-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v33 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index d8767137d9..abce06d046 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1309,6 +1309,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 97406b28c9..0ff5e3922b 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -105,6 +133,7 @@ typedef struct MV_TriggerTable TupleTableSlot *slot; /* for checking visibility in the pre-state table */ } MV_TriggerTable; +static HTAB *mv_query_cache = NULL; static HTAB *mv_trigger_info = NULL; static bool in_delta_calculation = false; @@ -165,6 +194,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -173,17 +205,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort); /* @@ -2122,6 +2167,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2203,6 +2250,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2232,6 +2290,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2250,10 +2310,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2445,6 +2513,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2547,19 +2679,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2574,10 +2731,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2585,10 +2743,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2771,6 +2944,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -2804,6 +3320,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -2812,6 +3335,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.25.1 --Multipart=_Tue__2_Jul_2024_17_03_11_+0900_6OrVBZxOB4o_k6A1 Content-Type: text/x-diff; name="v33-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v33-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v32 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index ecec93ec1c..d3cf3df5a7 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1311,6 +1311,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index b7f6c3831b..42ff0ed98f 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -105,6 +133,7 @@ typedef struct MV_TriggerTable TupleTableSlot *slot; /* for checking visibility in the pre-state table */ } MV_TriggerTable; +static HTAB *mv_query_cache = NULL; static HTAB *mv_trigger_info = NULL; static bool in_delta_calculation = false; @@ -165,6 +194,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -173,17 +205,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort); /* @@ -2124,6 +2169,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2205,6 +2252,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2234,6 +2292,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2252,10 +2312,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2447,6 +2515,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2549,19 +2681,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2576,10 +2733,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2587,10 +2745,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2773,6 +2946,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -2806,6 +3322,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -2814,6 +3337,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.25.1 --Multipart=_Sun__31_Mar_2024_22_59_31_+0900_msknEviJj08_wgqO Content-Type: text/x-diff; name="v32-0010-Add-regression-tests-for-Incremental-View-Mainte.patch" Content-Disposition: attachment; filename="v32-0010-Add-regression-tests-for-Incremental-View-Mainte.patch" Content-Transfer-Encoding: 7bit ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v34 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index d8767137d9..abce06d046 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1309,6 +1309,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index ca6d236989..8cd7ed3b68 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -105,6 +133,7 @@ typedef struct MV_TriggerTable TupleTableSlot *slot; /* for checking visibility in the pre-state table */ } MV_TriggerTable; +static HTAB *mv_query_cache = NULL; static HTAB *mv_trigger_info = NULL; static bool in_delta_calculation = false; @@ -165,6 +194,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -173,17 +205,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort); /* @@ -2124,6 +2169,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2205,6 +2252,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2234,6 +2292,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2252,10 +2312,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2447,6 +2515,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2549,19 +2681,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2576,10 +2733,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2587,10 +2745,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2773,6 +2946,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -2806,6 +3322,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -2814,6 +3337,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.34.1 --Multipart=_Thu__11_Jul_2024_13_23_57_+0900_hKsU2G3a3BgS2FFs Content-Type: text/x-diff; name="v34-0008-Add-aggregates-support-in-IVM.patch" Content-Disposition: attachment; filename="v34-0008-Add-aggregates-support-in-IVM.patch" Content-Transfer-Encoding: quoted-printable ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v30 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index d93eec3eec..0536e44b9e 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1312,6 +1312,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 3c523991ed..e60f92226c 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -73,6 +73,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -109,6 +137,7 @@ typedef struct MV_TriggerTable TupleTableSlot *slot; /* for checking visibility in the pre-state table */ } MV_TriggerTable; +static HTAB *mv_query_cache = NULL; static HTAB *mv_trigger_info = NULL; static bool in_delta_calculation = false; @@ -169,6 +198,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -177,17 +209,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort); /* @@ -2123,6 +2168,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2204,6 +2251,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2233,6 +2291,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2251,10 +2311,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2446,6 +2514,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2548,19 +2680,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2575,10 +2732,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2586,10 +2744,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2772,6 +2945,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -2805,6 +3321,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -2813,6 +3336,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.25.1 --Multipart=_Mon__4_Mar_2024_11_58_46_+0900_UaponF/qQhQrVCFt Content-Type: text/x-diff; name="v30-0010-Add-regression-tests-for-Incremental-View-Mainte.patch" Content-Disposition: attachment; filename="v30-0010-Add-regression-tests-for-Incremental-View-Mainte.patch" Content-Transfer-Encoding: 7bit ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v31 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index aa8440b4e1..7e1627ad1b 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1309,6 +1309,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index 97406b28c9..0ff5e3922b 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -69,6 +69,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -105,6 +133,7 @@ typedef struct MV_TriggerTable TupleTableSlot *slot; /* for checking visibility in the pre-state table */ } MV_TriggerTable; +static HTAB *mv_query_cache = NULL; static HTAB *mv_trigger_info = NULL; static bool in_delta_calculation = false; @@ -165,6 +194,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -173,17 +205,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort); /* @@ -2122,6 +2167,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2203,6 +2250,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2232,6 +2290,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2250,10 +2310,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2445,6 +2513,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2547,19 +2679,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2574,10 +2731,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2585,10 +2743,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2771,6 +2944,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -2804,6 +3320,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -2812,6 +3335,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.25.1 --Multipart=_Fri__29_Mar_2024_23_47_00_+0900_KGpmmDOIs1266Ib1 Content-Type: text/x-diff; name="v31-0010-Add-regression-tests-for-Incremental-View-Mainte.patch" Content-Disposition: attachment; filename="v31-0010-Add-regression-tests-for-Incremental-View-Mainte.patch" Content-Transfer-Encoding: 7bit ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v29 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index c8aa558f2e..c40ea6b2bc 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1312,6 +1312,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index ee41f0007d..eff512d40c 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -73,6 +73,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -109,6 +137,7 @@ typedef struct MV_TriggerTable TupleTableSlot *slot; /* for checking visibility in the pre-state table */ } MV_TriggerTable; +static HTAB *mv_query_cache = NULL; static HTAB *mv_trigger_info = NULL; static bool in_delta_calculation = false; @@ -169,6 +198,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -177,17 +209,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort); /* @@ -2101,6 +2146,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2182,6 +2229,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2211,6 +2269,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2229,10 +2289,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2424,6 +2492,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2526,19 +2658,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2553,10 +2710,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2564,10 +2722,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2750,6 +2923,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -2783,6 +3299,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -2791,6 +3314,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.25.1 --Multipart=_Mon__28_Aug_2023_11_52_52_+0900_hj6L5h176QaSGtg7 Content-Type: text/x-diff; name="v29-0010-Add-regression-tests-for-Incremental-View-Mainte.patch" Content-Disposition: attachment; filename="v29-0010-Add-regression-tests-for-Incremental-View-Mainte.patch" Content-Transfer-Encoding: 7bit ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v29 09/11] Add support for min/max aggregates for IVM @ 2023-05-31 11:58 Yugo Nagata <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Yugo Nagata @ 2023-05-31 11:58 UTC (permalink / raw) Supporting min and max is more complicated than count, sum, or avg. For an example of min, when tuples are inserted, the current min value in the view and the min value in the inseteted tuples are compared, then the smaller one is used as the latest min value. On the other hand, when tuples are deleted, if the current min value in the view equals to the min in the deleted tuples, we need re-computation the latest min value from base tables. Otherwise, the current value in the view remains. --- src/backend/commands/createas.c | 45 +++ src/backend/commands/matview.c | 644 +++++++++++++++++++++++++++++++- 2 files changed, 680 insertions(+), 9 deletions(-) diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c index c8aa558f2e..c40ea6b2bc 100644 --- a/src/backend/commands/createas.c +++ b/src/backend/commands/createas.c @@ -1312,6 +1312,51 @@ check_aggregate_supports_ivm(Oid aggfnoid) case F_AVG_FLOAT8: case F_AVG_INTERVAL: + /* min */ + case F_MIN_ANYARRAY: + case F_MIN_INT8: + case F_MIN_INT4: + case F_MIN_INT2: + case F_MIN_OID: + case F_MIN_FLOAT4: + case F_MIN_FLOAT8: + case F_MIN_DATE: + case F_MIN_TIME: + case F_MIN_TIMETZ: + case F_MIN_MONEY: + case F_MIN_TIMESTAMP: + case F_MIN_TIMESTAMPTZ: + case F_MIN_INTERVAL: + case F_MIN_TEXT: + case F_MIN_NUMERIC: + case F_MIN_BPCHAR: + case F_MIN_TID: + case F_MIN_ANYENUM: + case F_MIN_INET: + case F_MIN_PG_LSN: + + /* max */ + case F_MAX_ANYARRAY: + case F_MAX_INT8: + case F_MAX_INT4: + case F_MAX_INT2: + case F_MAX_OID: + case F_MAX_FLOAT4: + case F_MAX_FLOAT8: + case F_MAX_DATE: + case F_MAX_TIME: + case F_MAX_TIMETZ: + case F_MAX_MONEY: + case F_MAX_TIMESTAMP: + case F_MAX_TIMESTAMPTZ: + case F_MAX_INTERVAL: + case F_MAX_TEXT: + case F_MAX_NUMERIC: + case F_MAX_BPCHAR: + case F_MAX_TID: + case F_MAX_ANYENUM: + case F_MAX_INET: + case F_MAX_PG_LSN: return true; default: diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c index ee41f0007d..eff512d40c 100644 --- a/src/backend/commands/matview.c +++ b/src/backend/commands/matview.c @@ -73,6 +73,34 @@ typedef struct #define MV_INIT_QUERYHASHSIZE 16 +/* MV query type codes */ +#define MV_PLAN_RECALC 1 +#define MV_PLAN_SET_VALUE 2 + +/* + * MI_QueryKey + * + * The key identifying a prepared SPI plan in our query hashtable + */ +typedef struct MV_QueryKey +{ + Oid matview_id; /* OID of materialized view */ + int32 query_type; /* query type ID, see MV_PLAN_XXX above */ +} MV_QueryKey; + +/* + * MV_QueryHashEntry + * + * Hash entry for cached plans used to maintain materialized views. + */ +typedef struct MV_QueryHashEntry +{ + MV_QueryKey key; + SPIPlanPtr plan; + SearchPathMatcher *search_path; /* search_path used for parsing + * and planning */ +} MV_QueryHashEntry; + /* * MV_TriggerHashEntry * @@ -109,6 +137,7 @@ typedef struct MV_TriggerTable TupleTableSlot *slot; /* for checking visibility in the pre-state table */ } MV_TriggerTable; +static HTAB *mv_query_cache = NULL; static HTAB *mv_trigger_info = NULL; static bool in_delta_calculation = false; @@ -169,6 +198,9 @@ static void append_set_clause_for_sum(const char *resname, StringInfo buf_old, static void append_set_clause_for_avg(const char *resname, StringInfo buf_old, StringInfo buf_new, StringInfo aggs_list, const char *aggtype); +static void append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min); static char *get_operation_string(IvmOp op, const char *col, const char *arg1, const char *arg2, const char* count_col, const char *castType); static char *get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, @@ -177,17 +209,30 @@ static void apply_old_delta(const char *matviewname, const char *deltaname_old, List *keys); static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname); + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc); static void apply_new_delta(const char *matviewname, const char *deltaname_new, StringInfo target_list); static void apply_new_delta_with_count(const char *matviewname, const char* deltaname_new, List *keys, StringInfo target_list, StringInfo aggs_set, const char* count_colname); static char *get_matching_condition_string(List *keys); +static char *get_returning_string(List *minmax_list, List *is_min_list, List *keys); +static char *get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list); +static char *get_select_for_recalc_string(List *keys); +static void recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel); +static SPIPlanPtr get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes); +static SPIPlanPtr get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes); static void generate_equal(StringInfo querybuf, Oid opttype, const char *leftop, const char *rightop); static void mv_InitHashTables(void); +static SPIPlanPtr mv_FetchPreparedPlan(MV_QueryKey *key); +static void mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan); +static void mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type); static void clean_up_IVM_hash_entry(MV_TriggerHashEntry *entry, bool is_abort); /* @@ -2101,6 +2146,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n ListCell *lc; int i; List *keys = NIL; + List *minmax_list = NIL; + List *is_min_list = NIL; /* @@ -2182,6 +2229,17 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n append_set_clause_for_avg(resname, aggs_set_old, aggs_set_new, aggs_list_buf, format_type_be(aggref->aggtype)); + /* min/max */ + else if (!strcmp(aggname, "min") || !strcmp(aggname, "max")) + { + bool is_min = (!strcmp(aggname, "min")); + + append_set_clause_for_minmax(resname, aggs_set_old, aggs_set_new, aggs_list_buf, is_min); + + /* make a resname list of min and max aggregates */ + minmax_list = lappend(minmax_list, resname); + is_min_list = lappend_int(is_min_list, is_min); + } else elog(ERROR, "unsupported aggregate function: %s", aggname); } @@ -2211,6 +2269,8 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n if (old_tuplestores && tuplestore_tuple_count(old_tuplestores) > 0) { EphemeralNamedRelation enr = palloc(sizeof(EphemeralNamedRelationData)); + SPITupleTable *tuptable_recalc = NULL; + uint64 num_recalc; int rc; /* convert tuplestores to ENR, and register for SPI */ @@ -2229,10 +2289,18 @@ apply_delta(Oid matviewOid, Tuplestorestate *old_tuplestores, Tuplestorestate *n /* apply old delta and get rows to be recalculated */ apply_old_delta_with_count(matviewname, OLD_DELTA_ENRNAME, keys, aggs_list_buf, aggs_set_old, - count_colname); + minmax_list, is_min_list, + count_colname, &tuptable_recalc, &num_recalc); else apply_old_delta(matviewname, OLD_DELTA_ENRNAME, keys); + /* + * If we have min or max, we might have to recalculate aggregate values from base tables + * on some tuples. TIDs and keys such tuples are returned as a result of the above query. + */ + if (minmax_list && tuptable_recalc) + recalc_and_set_values(tuptable_recalc, num_recalc, minmax_list, keys, matviewRel); + } /* For tuple insertion */ if (new_tuplestores && tuplestore_tuple_count(new_tuplestores) > 0) @@ -2424,6 +2492,70 @@ append_set_clause_for_avg(const char *resname, StringInfo buf_old, ); } +/* + * append_set_clause_for_minmax + * + * Append SET clause string for min or max aggregation to given buffers. + * Also, append resnames required for calculating the aggregate value. + * is_min is true if this is min, false if not. + */ +static void +append_set_clause_for_minmax(const char *resname, StringInfo buf_old, + StringInfo buf_new, StringInfo aggs_list, + bool is_min) +{ + char *count_col = IVM_colname("count", resname); + + /* For tuple deletion */ + if (buf_old) + { + /* + * If the new value doesn't became NULL then use the value remaining + * in the view although this will be recomputated afterwords. + */ + appendStringInfo(buf_old, + ", %s = CASE WHEN %s THEN NULL ELSE %s END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_SUB, "mv", "t", count_col), + quote_qualified_identifier("mv", resname) + ); + /* count = mv.count - t.count */ + appendStringInfo(buf_old, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_SUB, count_col, "mv", "t", NULL, NULL) + ); + } + /* For tuple insertion */ + if (buf_new) + { + /* + * min = LEAST(mv.min, diff.min) + * max = GREATEST(mv.max, diff.max) + */ + appendStringInfo(buf_new, + ", %s = CASE WHEN %s THEN NULL ELSE %s(%s,%s) END", + quote_qualified_identifier(NULL, resname), + get_null_condition_string(IVM_ADD, "mv", "diff", count_col), + + is_min ? "LEAST" : "GREATEST", + quote_qualified_identifier("mv", resname), + quote_qualified_identifier("diff", resname) + ); + /* count = mv.count + diff.count */ + appendStringInfo(buf_new, + ", %s = %s", + quote_qualified_identifier(NULL, count_col), + get_operation_string(IVM_ADD, count_col, "mv", "diff", NULL, NULL) + ); + } + + appendStringInfo(aggs_list, ", %s, %s", + quote_qualified_identifier("diff", resname), + quote_qualified_identifier("diff", IVM_colname("count", resname)) + ); +} + /* * get_operation_string * @@ -2526,19 +2658,44 @@ get_null_condition_string(IvmOp op, const char *arg1, const char *arg2, * list to identify a tuple in the view. If the view has aggregates, this * requires strings representing resnames of aggregates and SET clause for * updating aggregate values. + * + * If the view has min or max aggregate, this requires a list of resnames of + * min/max aggregates and a list of boolean which represents which entries in + * minmax_list is min. These are necessary to check if we need to recalculate + * min or max aggregate values. In this case, this query returns TID and keys + * of tuples which need to be recalculated. This result and the number of rows + * are stored in tuptables and num_recalc repectedly. + * */ static void apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, List *keys, StringInfo aggs_list, StringInfo aggs_set, - const char *count_colname) + List *minmax_list, List *is_min_list, + const char *count_colname, + SPITupleTable **tuptable_recalc, uint64 *num_recalc) { StringInfoData querybuf; char *match_cond; + char *updt_returning = ""; + char *select_for_recalc = "SELECT"; bool agg_without_groupby = (list_length(keys) == 0); + Assert(tuptable_recalc != NULL); + Assert(num_recalc != NULL); + /* build WHERE condition for searching tuples to be deleted */ match_cond = get_matching_condition_string(keys); + /* + * We need a special RETURNING clause and SELECT statement for min/max to + * check which tuple needs re-calculation from base tables. + */ + if (minmax_list) + { + updt_returning = get_returning_string(minmax_list, is_min_list, keys); + select_for_recalc = get_select_for_recalc_string(keys); + } + /* Search for matching tuples from the view and update or delete if found. */ initStringInfo(&querybuf); appendStringInfo(&querybuf, @@ -2553,10 +2710,11 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, "UPDATE %s AS mv SET %s = mv.%s OPERATOR(pg_catalog.-) t.%s " "%s" /* SET clauses for aggregates */ "FROM t WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND NOT for_dlt " - ")" - /* delete a tuple if this is to be deleted */ - "DELETE FROM %s AS mv USING t " - "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt", + "%s" /* RETURNING clause for recalc infomation */ + "), dlt AS (" /* delete a tuple if this is to be deleted */ + "DELETE FROM %s AS mv USING t " + "WHERE mv.ctid OPERATOR(pg_catalog.=) t.ctid AND for_dlt" + ") %s", /* SELECT returning which tuples need to be recalculated */ count_colname, count_colname, count_colname, (agg_without_groupby ? "false" : "true"), (aggs_list != NULL ? aggs_list->data : ""), @@ -2564,10 +2722,25 @@ apply_old_delta_with_count(const char *matviewname, const char *deltaname_old, match_cond, matviewname, count_colname, count_colname, count_colname, (aggs_set != NULL ? aggs_set->data : ""), - matviewname); + updt_returning, + matviewname, + select_for_recalc); - if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE) + if (SPI_exec(querybuf.data, 0) != SPI_OK_SELECT) elog(ERROR, "SPI_exec failed: %s", querybuf.data); + + + /* Return tuples to be recalculated. */ + if (minmax_list) + { + *tuptable_recalc = SPI_tuptable; + *num_recalc = SPI_processed; + } + else + { + *tuptable_recalc = NULL; + *num_recalc = 0; + } } /* @@ -2750,6 +2923,349 @@ get_matching_condition_string(List *keys) return match_cond.data; } +/* + * get_returning_string + * + * Build a string for RETURNING clause of UPDATE used in apply_old_delta_with_count. + * This clause returns ctid and a boolean value that indicates if we need to + * recalculate min or max value, for each updated row. + */ +static char * +get_returning_string(List *minmax_list, List *is_min_list, List *keys) +{ + StringInfoData returning; + char *recalc_cond; + ListCell *lc; + + Assert(minmax_list != NIL && is_min_list != NIL); + recalc_cond = get_minmax_recalc_condition_string(minmax_list, is_min_list); + + initStringInfo(&returning); + + appendStringInfo(&returning, "RETURNING mv.ctid AS tid, (%s) AS recalc", recalc_cond); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + appendStringInfo(&returning, ", %s", quote_qualified_identifier("mv", resname)); + } + + return returning.data; +} + +/* + * get_minmax_recalc_condition_string + * + * Build a predicate string for checking if any min/max aggregate + * value needs to be recalculated. + */ +static char * +get_minmax_recalc_condition_string(List *minmax_list, List *is_min_list) +{ + StringInfoData recalc_cond; + ListCell *lc1, *lc2; + + initStringInfo(&recalc_cond); + + Assert (list_length(minmax_list) == list_length(is_min_list)); + + forboth (lc1, minmax_list, lc2, is_min_list) + { + char *resname = (char *) lfirst(lc1); + bool is_min = (bool) lfirst_int(lc2); + char *op_str = (is_min ? ">=" : "<="); + + appendStringInfo(&recalc_cond, "%s OPERATOR(pg_catalog.%s) %s", + quote_qualified_identifier("mv", resname), + op_str, + quote_qualified_identifier("t", resname) + ); + + if (lnext(minmax_list, lc1)) + appendStringInfo(&recalc_cond, " OR "); + } + + return recalc_cond.data; +} + +/* + * get_select_for_recalc_string + * + * Build a query to return tid and keys of tuples which need + * recalculation. This is used as the result of the query + * built by apply_old_delta. + */ +static char * +get_select_for_recalc_string(List *keys) +{ + StringInfoData qry; + ListCell *lc; + + initStringInfo(&qry); + + appendStringInfo(&qry, "SELECT tid"); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + appendStringInfo(&qry, ", %s", NameStr(attr->attname)); + } + + appendStringInfo(&qry, " FROM updt WHERE recalc"); + + return qry.data; +} + +/* + * recalc_and_set_values + * + * Recalculate tuples in a materialized from base tables and update these. + * The tuples which needs recalculation are specified by keys, and resnames + * of columns to be updated are specified by namelist. TIDs and key values + * are given by tuples in tuptable_recalc. Its first attribute must be TID + * and key values must be following this. + */ +static void +recalc_and_set_values(SPITupleTable *tuptable_recalc, int64 num_tuples, + List *namelist, List *keys, Relation matviewRel) +{ + TupleDesc tupdesc_recalc = tuptable_recalc->tupdesc; + Oid *keyTypes = NULL, *types = NULL; + char *keyNulls = NULL, *nulls = NULL; + Datum *keyVals = NULL, *vals = NULL; + int num_vals = list_length(namelist); + int num_keys = list_length(keys); + uint64 i; + Oid matviewOid; + char *matviewname; + + matviewOid = RelationGetRelid(matviewRel); + matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)), + RelationGetRelationName(matviewRel)); + + /* If we have keys, initialize arrays for them. */ + if (keys) + { + keyTypes = palloc(sizeof(Oid) * num_keys); + keyNulls = palloc(sizeof(char) * num_keys); + keyVals = palloc(sizeof(Datum) * num_keys); + /* a tuple contains keys to be recalculated and ctid to be updated*/ + Assert(tupdesc_recalc->natts == num_keys + 1); + + /* Types of key attributes */ + for (i = 0; i < num_keys; i++) + keyTypes[i] = TupleDescAttr(tupdesc_recalc, i + 1)->atttypid; + } + + /* allocate memory for all attribute names and tid */ + types = palloc(sizeof(Oid) * (num_vals + 1)); + nulls = palloc(sizeof(char) * (num_vals + 1)); + vals = palloc(sizeof(Datum) * (num_vals + 1)); + + /* For each tuple which needs recalculation */ + for (i = 0; i < num_tuples; i++) + { + int j; + bool isnull; + SPIPlanPtr plan; + SPITupleTable *tuptable_newvals; + TupleDesc tupdesc_newvals; + + /* Set group key values as parameters if needed. */ + if (keys) + { + for (j = 0; j < num_keys; j++) + { + keyVals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, j + 2, &isnull); + if (isnull) + keyNulls[j] = 'n'; + else + keyNulls[j] = ' '; + } + } + + /* + * Get recalculated values from base tables. The result must be + * only one tuple thich contains the new values for specified keys. + */ + plan = get_plan_for_recalc(matviewOid, namelist, keys, keyTypes); + if (SPI_execute_plan(plan, keyVals, keyNulls, false, 0) != SPI_OK_SELECT) + elog(ERROR, "SPI_execute_plan"); + if (SPI_processed != 1) + elog(ERROR, "SPI_execute_plan returned zero or more than one rows"); + + tuptable_newvals = SPI_tuptable; + tupdesc_newvals = tuptable_newvals->tupdesc; + + Assert(tupdesc_newvals->natts == num_vals); + + /* Set the new values as parameters */ + for (j = 0; j < tupdesc_newvals->natts; j++) + { + if (i == 0) + types[j] = TupleDescAttr(tupdesc_newvals, j)->atttypid; + + vals[j] = SPI_getbinval(tuptable_newvals->vals[0], tupdesc_newvals, j + 1, &isnull); + if (isnull) + nulls[j] = 'n'; + else + nulls[j] = ' '; + } + /* Set TID of the view tuple to be updated as a parameter */ + types[j] = TIDOID; + vals[j] = SPI_getbinval(tuptable_recalc->vals[i], tupdesc_recalc, 1, &isnull); + nulls[j] = ' '; + + /* Update the view tuple to the new values */ + plan = get_plan_for_set_values(matviewOid, matviewname, namelist, types); + if (SPI_execute_plan(plan, vals, nulls, false, 0) != SPI_OK_UPDATE) + elog(ERROR, "SPI_execute_plan"); + } +} + + +/* + * get_plan_for_recalc + * + * Create or fetch a plan for recalculating value in the view's target list + * from base tables using the definition query of materialized view specified + * by matviewOid. namelist is a list of resnames of values to be recalculated. + * + * keys is a list of keys to identify tuples to be recalculated if this is not + * empty. KeyTypes is an array of types of keys. + */ +static SPIPlanPtr +get_plan_for_recalc(Oid matviewOid, List *namelist, List *keys, Oid *keyTypes) +{ + MV_QueryKey hash_key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the recalculation */ + mv_BuildQueryKey(&hash_key, matviewOid, MV_PLAN_RECALC); + if ((plan = mv_FetchPreparedPlan(&hash_key)) == NULL) + { + ListCell *lc; + StringInfoData str; + char *viewdef; + + /* get view definition of matview */ + viewdef = text_to_cstring((text *) DatumGetPointer( + DirectFunctionCall1(pg_get_viewdef, ObjectIdGetDatum(matviewOid)))); + /* get rid of trailing semi-colon */ + viewdef[strlen(viewdef)-1] = '\0'; + + /* + * Build a query string for recalculating values. This is like + * + * SELECT x1, x2, x3, ... FROM ( ... view definition query ...) mv + * WHERE (key1, key2, ...) = ($1, $2, ...); + */ + + initStringInfo(&str); + appendStringInfo(&str, "SELECT "); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, " FROM (%s) mv", viewdef); + + if (keys) + { + int i = 1; + char paramname[16]; + + appendStringInfo(&str, " WHERE ("); + foreach (lc, keys) + { + Form_pg_attribute attr = (Form_pg_attribute) lfirst(lc); + char *resname = NameStr(attr->attname); + Oid typid = attr->atttypid; + + sprintf(paramname, "$%d", i); + appendStringInfo(&str, "("); + generate_equal(&str, typid, resname, paramname); + appendStringInfo(&str, " OR (%s IS NULL AND %s IS NULL))", + resname, paramname); + + if (lnext(keys, lc)) + appendStringInfoString(&str, " AND "); + i++; + } + appendStringInfo(&str, ")"); + } + else + keyTypes = NULL; + + plan = SPI_prepare(str.data, list_length(keys), keyTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&hash_key, plan); + } + + return plan; +} + +/* + * get_plan_for_set_values + * + * Create or fetch a plan for applying new values calculated by + * get_plan_for_recalc to a materialized view specified by matviewOid. + * matviewname is the name of the view. namelist is a list of resnames + * of attributes to be updated, and valTypes is an array of types of the + * values. + */ +static SPIPlanPtr +get_plan_for_set_values(Oid matviewOid, char *matviewname, List *namelist, + Oid *valTypes) +{ + MV_QueryKey key; + SPIPlanPtr plan; + + /* Fetch or prepare a saved plan for the real check */ + mv_BuildQueryKey(&key, matviewOid, MV_PLAN_SET_VALUE); + if ((plan = mv_FetchPreparedPlan(&key)) == NULL) + { + ListCell *lc; + StringInfoData str; + int i; + + /* + * Build a query string for applying min/max values. This is like + * + * UPDATE matviewname AS mv + * SET (x1, x2, x3, x4) = ($1, $2, $3, $4) + * WHERE ctid = $5; + */ + + initStringInfo(&str); + appendStringInfo(&str, "UPDATE %s AS mv SET (", matviewname); + foreach (lc, namelist) + { + appendStringInfo(&str, "%s", (char *) lfirst(lc)); + if (lnext(namelist, lc)) + appendStringInfoString(&str, ", "); + } + appendStringInfo(&str, ") = ROW("); + + for (i = 1; i <= list_length(namelist); i++) + appendStringInfo(&str, "%s$%d", (i==1 ? "" : ", "), i); + + appendStringInfo(&str, ") WHERE ctid OPERATOR(pg_catalog.=) $%d", i); + + plan = SPI_prepare(str.data, list_length(namelist) + 1, valTypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), str.data); + + SPI_keepplan(plan); + mv_HashPreparedPlan(&key, plan); + } + + return plan; +} + /* * generate_equals * @@ -2783,6 +3299,13 @@ mv_InitHashTables(void) { HASHCTL ctl; + memset(&ctl, 0, sizeof(ctl)); + ctl.keysize = sizeof(MV_QueryKey); + ctl.entrysize = sizeof(MV_QueryHashEntry); + mv_query_cache = hash_create("MV query cache", + MV_INIT_QUERYHASHSIZE, + &ctl, HASH_ELEM | HASH_BLOBS); + memset(&ctl, 0, sizeof(ctl)); ctl.keysize = sizeof(Oid); ctl.entrysize = sizeof(MV_TriggerHashEntry); @@ -2791,6 +3314,109 @@ mv_InitHashTables(void) &ctl, HASH_ELEM | HASH_BLOBS); } +/* + * mv_FetchPreparedPlan + */ +static SPIPlanPtr +mv_FetchPreparedPlan(MV_QueryKey *key) +{ + MV_QueryHashEntry *entry; + SPIPlanPtr plan; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Lookup for the key + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_FIND, NULL); + if (entry == NULL) + return NULL; + + /* + * Check whether the plan is still valid. If it isn't, we don't want to + * simply rely on plancache.c to regenerate it; rather we should start + * from scratch and rebuild the query text too. This is to cover cases + * such as table/column renames. We depend on the plancache machinery to + * detect possible invalidations, though. + * + * CAUTION: this check is only trustworthy if the caller has already + * locked both materialized views and base tables. + * + * Also, check whether the search_path is still the same as when we made it. + * If it isn't, we need to rebuild the query text because the result of + * pg_ivm_get_viewdef() will change. + */ + plan = entry->plan; + if (plan && SPI_plan_is_valid(plan) && + SearchPathMatchesCurrentEnvironment(entry->search_path)) + return plan; + + /* + * Otherwise we might as well flush the cached plan now, to free a little + * memory space before we make a new one. + */ + if (plan) + SPI_freeplan(plan); + if (entry->search_path) + pfree(entry->search_path); + + entry->plan = NULL; + entry->search_path = NULL; + + return NULL; +} + +/* + * mv_HashPreparedPlan + * + * Add another plan to our private SPI query plan hashtable. + */ +static void +mv_HashPreparedPlan(MV_QueryKey *key, SPIPlanPtr plan) +{ + MV_QueryHashEntry *entry; + bool found; + + /* + * On the first call initialize the hashtable + */ + if (!mv_query_cache) + mv_InitHashTables(); + + /* + * Add the new plan. We might be overwriting an entry previously found + * invalid by mv_FetchPreparedPlan. + */ + entry = (MV_QueryHashEntry *) hash_search(mv_query_cache, + (void *) key, + HASH_ENTER, &found); + Assert(!found || entry->plan == NULL); + entry->plan = plan; + entry->search_path = GetSearchPathMatcher(TopMemoryContext); +} + +/* + * mv_BuildQueryKey + * + * Construct a hashtable key for a prepared SPI plan for IVM. + */ +static void +mv_BuildQueryKey(MV_QueryKey *key, Oid matview_id, int32 query_type) +{ + /* + * We assume struct MV_QueryKey contains no padding bytes, else we'd need + * to use memset to clear them. + */ + key->matview_id = matview_id; + key->query_type = query_type; +} + /* * AtAbort_IVM * -- 2.25.1 --Multipart=_Mon__28_Aug_2023_16_05_30_+0900_b1OvQD_3A3ZMTGvj Content-Type: text/x-diff; name="v29-0010-Add-regression-tests-for-Incremental-View-Mainte.patch" Content-Disposition: attachment; filename="v29-0010-Add-regression-tests-for-Incremental-View-Mainte.patch" Content-Transfer-Encoding: 7bit ^ permalink raw reply [nested|flat] 259+ messages in thread
* [PATCH v2 4/7] Row pattern recognition patch (executor). @ 2023-06-26 08:05 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 259+ messages in thread From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 225 +++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 302 ++++++++++++++++++++++++++- src/include/catalog/pg_proc.dat | 9 + src/include/nodes/execnodes.h | 13 ++ src/include/windowapi.h | 9 + 5 files changed, 548 insertions(+), 10 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..bef2bc62b2 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -48,6 +48,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +160,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -195,9 +204,9 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -2388,6 +2397,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2498,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2692,71 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + if (func->winfnoid != F_RPR) + continue; + + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "RPR must have 1 argument but function %d has %d args", func->winfnoid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "RPR's arg is not Var"); + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2764,76 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2851,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2902,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3244,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3420,14 +3584,53 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3583,15 +3786,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3823,9 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..74ef11ce55 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,10 +39,21 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - +static bool get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos); +static int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result); /* * utility routine for *_rank functions. @@ -713,3 +727,289 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * rpr + * allow to use "Row pattern recognition: WINDOW clause" (SQL:2016 R020) in + * the target list. + * Usage: SELECT rpr(colname) OVER (..) + * where colname is defined in PATTERN clause. + */ +Datum +window_rpr(PG_FUNCTION_ARGS) +{ +#define MAX_PATTERNS 16 /* max variables in PATTERN clause */ + + WindowObject winobj = PG_WINDOW_OBJECT(); + WindowAggState *winstate = WinGetAggState(winobj); + Datum result; + bool expression_result; + bool isnull; + int relpos; + int64 curr_pos, markpos; + ListCell *lc, *lc1; + SkipContext *context = NULL; + + curr_pos = WinGetCurrentPosition(winobj); + elog(DEBUG1, "rpr is called. row: " INT64_FORMAT, curr_pos); + + if (winstate->rpSkipTo == ST_PAST_LAST_ROW) + { + context = (SkipContext *) WinGetPartitionLocalMemory(winobj, sizeof(SkipContext)); + if (curr_pos < context->pos) + { + elog(DEBUG1, "skip this row: curr_pos: " INT64_FORMAT "context->pos: " INT64_FORMAT, + curr_pos, context->pos); + PG_RETURN_NULL(); + } + } + + /* + * Evaluate PATTERN until one of expressions is not true or out of frame. + */ + relpos = 0; + + forboth(lc, winstate->patternVariableList, lc1, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc)); + char *quantifier = strVal(lfirst(lc1)); + + elog(DEBUG1, "relpos: %d pattern vname: %s quantifier: %s", relpos, vname, quantifier); + + /* evaluate row pattern against current row */ + relpos = evaluate_pattern(winobj, winstate, relpos, vname, quantifier, &expression_result); + + /* + * If the expression did not match, we are done. + */ + if (!expression_result) + break; + + /* out of frame? */ + if (relpos < 0) + break; + + /* count up relative row position */ + relpos++; + } + + elog(DEBUG1, "relpos: %d", relpos); + + /* + * If current row satified the pattern, return argument expression. + */ + if (expression_result) + { + result = WinGetFuncArgInFrame(winobj, 0, + 0, WINDOW_SEEK_HEAD, false, + &isnull, NULL); + } + + /* + * At this point we can set mark down to current pos -2. + */ + markpos = curr_pos -2; + elog(DEBUG1, "markpos: " INT64_FORMAT, markpos); + if (markpos >= 0) + WinSetMarkPosition(winobj, markpos); + + if (expression_result) + { + if (winstate->rpSkipTo == ST_PAST_LAST_ROW) + { + context->pos += relpos; + elog(DEBUG1, "context->pos: " INT64_FORMAT, context->pos); + } + PG_RETURN_DATUM(result); + } + + PG_RETURN_NULL(); +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match relative row position + * -1: current row is out of frame + */ +static +int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result) +{ + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + int sts; + bool out_of_frame = false; + bool isnull; + StringInfo encoded_str = makeStringInfo(); + char pattern_str[128]; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + bool second_try_match = false; + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + for (;;) + { + if (!get_slots(winobj, winstate, relpos)) + { + out_of_frame = true; + break; /* current row is out of frame */ + } + + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: %d", vname, relpos); + break; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: %d", vname, relpos); + break; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: %d", vname, relpos); + appendStringInfoChar(encoded_str, vname[0]); + + /* If quantifier is "+", we need to look for more matching row */ + if (quantifier && !strcmp(quantifier, "+")) + { + /* remember that we want to try another row */ + second_try_match = true; + relpos++; + } + else + break; + } + } + } + if (second_try_match) + relpos--; + + if (out_of_frame) + { + *result = false; + return -1; + } + + /* build regular expression */ + snprintf(pattern_str, sizeof(pattern_str), "%c%s", vname[0], quantifier); + + /* + * Do regular expression matching against sequence of rows satisfying + * the expression using regexp_instr(). + */ + sts = DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str->data)), + PointerGetDatum(cstring_to_text(pattern_str)))); + elog(DEBUG1, "regexp_instr returned: %d. str: %s regexp: %s", + sts, encoded_str->data, pattern_str); + *result = (sts > 0)? true : false; + } + return relpos; +} + +/* + * Get current, previous and next tuple. + * Returns true if still within frame. + */ +static bool +get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos) +{ + TupleTableSlot *slot; + bool isnull, isout; + int sts; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* for current row */ + slot = winstate->temp_slot_1; + sts = WinGetSlotInFrame(winobj, slot, + current_pos, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "current row is out of frame"); + econtext->ecxt_scantuple = winstate->null_slot; + return false; + } + else + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos - 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "previous row out of frame at: %d", current_pos); + econtext->ecxt_outertuple = winstate->null_slot; + } + econtext->ecxt_outertuple = slot; + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos + 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "next row out of frame at: %d", current_pos); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + + return true; +} + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..e3a9e0ffeb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,15 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'row pattern recognition in window', + proname => 'rpr', prokind => 'w', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_rpr' }, +{ oid => '6123', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6124', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..1643eaa6f1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,14 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2563,11 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..a0facf38fe 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,16 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Mon_Jun_26_17_45_07_2023_724)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v2-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 259+ messages in thread
end of thread, other threads:[~2023-06-26 08:05 UTC | newest] Thread overview: 259+ messages (download: mbox mbox.gz follow: Atom feed) -- links below jump to the message on this page -- 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v33 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v30 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v29 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v31 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v29 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v28 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v34 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v32 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v38 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-05-31 11:58 [PATCH v37 09/11] Add support for min/max aggregates for IVM Yugo Nagata <[email protected]> 2023-06-26 08:05 [PATCH v2 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]>
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